Shuttleless looms with continuous weft feeding



May 15, 1956 R. DEWAS 2,745,440

SHUTTLELESS LOOMS WITH cowsziquous WEFT FEEDING Filed Feb. 18, 1952 6 Sheets-Sheet l TNVENTOR: lea a mond 0a was OLV QPL QM ATTOI' N E35 May 15, 1956 R DEWAS 2,745,440

SHUTTLELESS LOOMS WITH CONTINUOUS WEFT FEEDING Filed Feb. 18, 1952 6 Sheets-Sheet 2 wvemotz- Rggmonc/ pea/as l3 GLLMLW ATTO (LN 59S May 15, 1956 R. DEWAS 2,745,440

SHUTTLELESS LOOMS WITH CONTINUOUS WEFT FEEDING Filed Feb. 18, 1952 6 Sheets-Sheet 3 INVENTOR'. j/" d ewas ATTOFLNFSg SHUTTLELESS LOGMS WITH CONTINUOUS WEFT FEEDING Filed Feb. 18, 1952 6 Sheets-Sheet 5 INVEN Ra /mend 08 was MAL R. DEWAS May 15, 1956 SHUTTLELESS LOOMS WITH CONTINUOUS WEFT FEEDING 6 Sheets-Sheet 6 I NVENTOTL Rqflmonc/ DEh/as QEW Filed Feb. 18. 1952 m Qw wwm Gwwn gm ATTQRNEHS United States Patent SHUTTLELESS LOOMS WITH ONTINUOUS WEFT FEEDENG Raymond Dewas, Amiens, France Application February 13, 1952, Serial No. 272,049

Claims priority, application Great Britain February 23, 1951 4 Claims. (Cl. 139-123) This invention relates to improvements in shuttleless weaving looms with continuous weft feeding, and has reference to weft feeder looms without pirn, of the kind in which the weft is inserted either by a single weft feeder or needle, or two oppositely arranged weft feeders or needles, one of which conducts the weft to the middle of the shed where it is taken up'and drawn by the other to the selvedge.

The invention has reference to the movement of the single picking arm, or of the two oppositely arranged picking arms, positively operating the needle or needles for the insertion of the shoot, the picking arm or each one of the picking arms being positively driven, for instance, by a cam provided with a helicoidal groove co-operating with a roller, the shaft of which is fixed to the lower end of the picking arm.

The great speeds now reached by this kind of loom impose important stress on the cam, the roller and its shaft, owing to the accelerations and decelerations that occur.

The principal object of the invention is to reduce the fatigue of these members to a considerable extent and modify the profile of the cam to increase the rapidity of the accelerations anddecelerations, so that the extents of the idle periods are reduced, with the result that the cycle of operation is utilized more eifectively, and the maximum instantaneous speed of the needles is reduced, thus bringing about, among other things, a reduction in weft breakages.

According to this invention, the positively operated picking arm is submitted to the action of one torsion bar or/ and torsion tube, or of several of them, the torsion bar or tube being placed preferably in the centre of the shaft, hollowed to that effect, around which the picking arm oscillates. In that case, the bar is fixed at one of its ends to the end of the shaft, or to an extension of a part supporting said shaft or the oscillating picking arm, or still, mounted in an independent carrier, whilst the other end of said torsionbar is attached to the hub of the picking arm.

The picking arm can be submitted to the influence of the torsion bar only on certain portions of its stroke; for this purpose, one or the other of the ends of this bar and/ or a co-operating of the picking arm or of its oscillation shaft can be fitted with any mechanical, hydraulic or other suitable device.

it will be realized that, during speed reduction, a large part of the kinetic energy of the picking arm and of the needle, energy which it is thought advisable to compensate for avoiding thefatigue and wear of the parts, is stored in the torsion bar, which restores it on the n Xi acceleration to the picking arm, with the result of economy of motive force and possibility of increasing speed.

011 stopping the loom, the torsion bar may be discon nected either automatically or by hand, to enable the loom to be turned conveniently by hand, and on starting the loom again, reengagement may be automatic.

It is to be understood that the principle described above is applicable more particularly, either to a picking arm operating a needle by means of a small rod, or to a picking arm driving the needle by different means, or to a picking arm driving two oppositely arranged needles by. a known articulation system, or to a picking arm ofwhich the upper part consists of a toothed sector intended to set in action the pinion fixedon the shaft of a wheel which drives a band or ribbon to needle is fixed.

Other characteristics and advantages of the invention will also be found in the following description of one form v of construction which is given simply by way of a nonlimitative example and is diagrammatically shown in the attached drawings, in which:

Fig. 1 is a part sectional front elevation of the end of a batten of a loom with oppositely arranged weft inserters or needles showing a picking arm, the driving members therefor and its osciilating casing with its cover removed;

Fig. 5 is an end view showing the mounting of the rear end of the torsion bar;

Fig. 6 is a horizontal sectional view taken onthe line ViVl of Pig. 5;

Fig. 7 is a vertical sectional view, similar to Fig. 4,

showing another embodiment of the mountingofv the torsion bar; r

Fig. 8 is a plan view, similar to Fig. 3, showing an 7 embodiment comprising two cooperating torsion bars; Fig. 9 is an elevational side view, showing a torsion bar of great length cooperating at'its rear end with guiding means provided on a stationary carrier, independent with respect to the casing;

Fig. 10 is a sectional View taken on the line X--X of Fig. 9.

In the drawings, 1 is the batten having the channel Zin which slides the weft inserter or needle, not shown, 'operated by the picking arm 3 by means of the connecting rod 4. i

The batten iis attached to the swords 5 so that it can pivot about the axis of the lower shaft 6 supported by,

bearings 7 carried on the frame 8. I v, The casing 9 is rotatably mounted on the lower shaft 6 so that it can pivot freely thereon, the end platesf9a of the casing 9 forming bearings therefon'v The casing 9' is arranged to partake of the oscillating movement of the batten 1 by a connection'consisting, in the example shown,

of a crosspiece fixed at'll to the sword Sand at 12 to the flange 912 that rejects upwardly from the casing 9.

Within the casing 9 is arranged the cam 13 that is.

keyed on'the lower rotating shaft'6 and is provided with an endless helicoidal groove 14 "that engages with a roller 15 the spindle 16 of which is mounted in the lower, end of the picking arm 3. The extreme positions taken;-

by this roller, in the movement imparted to it by the groove 14, are indicated in Fig. 1 at 15' and 15", whilst the corresponding positions of the picking arm 3 are inf dicated by the chain lines 3' and 3" in that figure.

The casing 9 consists of a body, the profile of which is clearly shown in Fig. 2, having a front opening which is closed by a cover 17. i

The picking arm is oscillatingly mounted on Patented May 15, 1956 which the weft feeder or.

, 3 upperrparti of the casing 9 fromwhich it emerges at the location of the mounting.

According to the invention, the picking arm 3 is submitted to the action of one torsion bar or/and torsion tube; or of several 'of them.

In: the embodiment shown in Figs. lto 6, the picking arm :is' oscillatingly mounted on a tubular shaft through which passes a torsion bar, the fore end of which is connected tothe picking arm 'whilst its rear end'ismounted between abutting members made integral with thecasing.

The hub 3a of the picking armfi is mounted, through interposition of abearing 18,-'ona tubular shaft 19 fitted by means of nut and counter-nut 20. The torsion barfizlpassing through the tubular shaft 19 is fixed in positiomat its fore end, by a grooved jointing 22 in a cap 23 secured by nuts 24' to the hub 3a of the picking arm- 3; Thebar 21 is prevented from being longitudinally moved by means of screws 25 applying" a' cover 26 against cap 23. At'its rear'end, the baris shaped toi-form'projections 27 which are placed between abutting membersf28 made integral with a flange 29, secured by bolts =30-at one end of a tubular'casing 31, which is flared towards itsother end in order tobe attached to casing 9. Thismounting is such that'the projections 27 of the torsion: bar 21 and the abutments 28 are providedand arranged in such a manner that the torsion bar-comes into.- abutment only after having-performed a certain angular movement. The tubular casing may comprise one onseveral struts fixed, for instance, at'the rear ofthe casing. V

Regarding the modificationof the mounting, shown at'Figs 7, the torsion bar 21a'is, at its fore end, fixed in position, in the -sam'e way as. above described, on a cap 23a, but the height of said cap has been'made longer in order to increase correspondingly the length ofitli'e barf At its rear end, the" flange 2911, having abutments 28a, is secured to theend of the tubular axle 19d whichhas been extended for that purpose.

In certain cases, the torsion bar 21a may be rigidly fixed, at its rear :end, to the tubular shaft 19a in the same way ash is fixed at its fore end on the cap 23a whichIis-made integral with the hub of the picking arm.

In the various, embodiments'described herebelow, the dimensions and the material of the tubular members 31 and 19-respectively forming the carrier of the rear end of the torsion bar 21, may be'chosen'in such a manner that said tubular member, under the action of said bar 21, acts too as a tubular torsion bar.

Regard-ingtthe' embodiment 0f Fig. 8, the torsion bar 21b is combined with a second torsion bar 32b the rear endof which is coupled with the rear endof bar 21b by bevel wheels 33b and 34b mounted on respective;

grooves 35b and, 36b formed on said bars; P The other endv of the bar- 32b is fixed in'posifion by a grooved jointing 37b' in a carrier 38b formed integral with the tubular casing 31b. The bar 32b may occasionally be longer and fixed at the fore part, of the casing 9b. Th

bevel wheels may be cut into the torsion bars.

Inthe embodiment of Figs. 9 and v10, the. torsion bar V 21? having a great length, is fixedat its fore end on a part made integral withthe picking arm, asabove describedwithreference to Fig. 4. At its rear end, it com prises arectangular head 380 the upper andlower-parts of which, respectively shown at 38'21 and '38b,fare in the shapeiof portions of cylinders. This head is mounted on a guiding bore-39c ofa stationary carrier 400. In that way,fltliebari 21 is tightly guided while being able to slightly'gdforward and backward according to the movementsof the'casing 9c; 38'0 and 38c are respectively the'positions ofthe head 38- when the casing is in the extreme'positions shown by the correspondingpositions 17's and 17-'c of 'itsjcover. A fork 410 may. be provided I to "guide the. bar21c'at its middle portion.v

When thei'casing 9c coming fromits middle position He is oscillating rearwardly up to.17"c, the head38jc .4 1 moves up to 38"c andacts on the bar in such a manner that it is deflected along'the line 21"c. In that way, the bar acts as a torsion bar and flexion bar.

The operation is the same when the casing, leaving v 1 again its middle position 17c and oscillating forwardly up to 17c, the head 38c moves up to 38'c and acts on the bar in such a manner that said bar is deflected along the line 21'c. When-deflecting about the ends of its'strok'es, the bar stores up the kinetic energy of'the casing and of the picking arm, when they are oscillating forwardly and rearwardly, and then gives said energy back at the be inning. of the following oscillation;

It is possible to increase or decrease the the bar by directing differently the guiding bore 39c. It is also possible to suppress thedeflection by making the guiding bore movable, foriinstan'ce under the action of a cam. This cam would transfer the Center 420 of-the head 380 to the respective positions 42's and 42c,:when the casing would go from 17c to respectively 17'c' and 17c, the points 42c, 42c and 4 c being on an arc of a circle described by taking 'as'a centre the pivoting point 60 of'the casing 90. e

It is obvious that many variations and modifications may be resorted to by those skilled in the art without departing from'the scope of this invention as disclosed in the present specification-and defined by the appended claims.

Thus, the torsion bar, instead of being'made integral with the hub of the picking'arm by means of the cap 23," may be fixed to an axle passing throughthe hub of the picking arm, the shaft about which'the picking arm 0s.-

'cillates being provided with'ports enabling the picking arm" to be oscillated in spite of the axle.

The torsion bar may be made integral with the pick ing ram to operate as a shaft, for said pickingjarm, one or more bearings being then provided for carrying the bar. I

may have their position made adjustable, by screw or otherwise f J In the embodiments of Fig.8, the bevel Wheels may be changed'for toothed 'secto'rsior any other suitable members transmitting the rotations of'the bar Zlb. On;

the other hand, instead of a single torsion bar such as 32b, it is possible to provide several such bars, symmetrically or not symmetrically, arranged with respect to the I main bar 21b.

What i claimis:

end thereofto said hub, and retaining means carried by said loom and connected to the other end of said torsion bar, said means being adapted to prevent any rotational movement of said other end of said torsion bar. v

2. The cornbinatio'n'of claii'n'l, whe'reinfsaidretaining means are constituted by a tubular casing surrounding said torsion bar and having one end thereof fixedly secured to said main casing and the other end thereoffad-if iacent and secured to said other end of said torsion bar.

3. In a shuttleless loom comprising, a batten, an. oscillating picking arm, and a sword carryingsaid batten; a lower shaft, a casing rotatably mounted uponsaid lower shaft, a cross piece connecting said casing with said' sword,

cam keyed upon said lower shaft and locatedwithin said casing, said cam having a helicoidal groove formed therein, a roller carried by said pickinga'rm and located in said helicoidal groove, said picking arm having a hub, a T tubular shaft carrying said hub, an elongated torsion I bar extending through said tubular shaft, means firmly deflection of Theabutments 28 of the rear end of the torsion'bar' connecting said hub and one end of said torsion bar, an independent stationary carrier having a movable guiding bore formed therein, and means adjusting the direction of said movable bore according to the position of said carrier, the other end of said torsion bar being longitudinally movable in said bore.

4. In a shuttleless loom comprising a batten, an oscillating picking arm, and a sword carrying said batten; a lower shaft, a casing rotatably mounted upon said lower shaft, a cross piece connecting said casing with said sword, a cam keyed upon said lower shaft and located Within said casing, said cam having a helicoidal groove formed therein, a roller carried by said picking arm and located in said helicoidal groove, said picking arm having a hub, a tubular shaft carrying said hub, and a torsion bar combination comprising a torsion bar located in the center of said tubular shaft, and at least one auxiliary torsion bar having one end connected with the first-mentioned torsion bar, one end of said torsion bar combination being firmly connected with said hub, the other end of said torsion bar combination being firmly connected with said tubular shaft.

References Cited in the file of this patent UNITED STATES PATENTS 

